Gas leak is as bad as coal, says study – 07/19/2023 – Environment

Natural gas, long considered a cleaner alternative to coal and an important tool in the fight to slow global warming, could be just as damaging to the climate, a new study concludes, unless companies can eliminate the leaks that are common in its use.

It only takes 0.2% of natural gas to leak for it to become as big a climate change driver as coal, according to the study. That’s a small margin of error for a gas known to leak from drilling sites, processing plants and the pipelines that carry it to power plants or homes and kitchens.

Bottom line: If the gas leaks even a little bit, “it’s as bad as coal,” said Deborah Gordon, lead researcher and environmental policy expert at Brown University and the Rocky Mountain Institute, an energy-focused nonprofit research organization. clean. “It cannot be considered a good bridge, or replacement.”

The peer-reviewed study, which also involved researchers from Harvard and Duke universities and NASA and will be published this week in the journal Environmental Research Letters, adds to a substantial body of research that disputes the idea that natural gas is a suitable transition fuel for a future powered entirely by renewable energies such as solar and wind.

The findings raise difficult questions about how much more money countries should invest in gas infrastructure to avoid the worst of global warming.

The $370 billion Inflation Reduction Act passed by Congress last year, designed to move the country away from fossil fuels and towards renewables, includes credits that would apply to some forms of natural gas.

When power companies generate electricity by burning natural gas instead of coal, they emit only about half the amount of carbon dioxide that warms the planet.

In the United States, the shift from coal to gas, driven by a boom in oil and gas fracking, has helped reduce carbon emissions from power plants by nearly 40% since 2005.

But natural gas is mostly methane, which is a much more potent short-term planet-warming gas than carbon dioxide when it escapes unburned into the atmosphere.

And there is growing evidence that methane is doing just that: leaking out of gas systems in much larger amounts than previously thought. Infrared sensors and cameras are helping to visualize substantial methane leaks from oil and gas infrastructure, and increasingly powerful satellites are detecting episodes of “super-emissions”.

The latest study advances that science in several ways. It considered and compared the entire “lifecycle” of natural gas and coal emissions, from drilling and mining the fuel to distribution and burning.

The researchers also looked at natural gas and coal in all of their energy uses beyond electricity generation. Gas, in particular, is widely used as an industrial, commercial, and residential energy source for fuel, steam, heat, and power.

There are other tradeoffs to consider. The carbon dioxide expelled copiously by coal-burning plants lasts much longer in the atmosphere than methane, which dissipates after a few decades.

Therefore, focusing on methane leaks from gas infrastructure, at the expense of controlling carbon emissions, means that the world can mitigate some warming in the short term, but still face a dangerous increase in average temperatures many decades from now.

That said, with the consequences of climate change already wreaking havoc around the world, controlling methane would be a more immediate way to slow warming.

Pressured about its climate footprint, the oil and gas industry said it had made progress in detecting and eliminating unauthorized emissions. Independent monitoring and verification of these claims will be crucial, experts say.

Robert Howarth, an Earth systems scientist at Cornell University who raised the alarm about methane leaks more than a decade ago, called the analysis solid.

“Their conclusion is to point out again that natural gas may not be better for the climate than coal, particularly when viewed through the lens of warming over the next 20 years or so, which is obviously a critical time” to comply. climate targets, he said in an email.

“I hope the policy world and political leaders heed this, as I fear many remain obsessed with simply reducing coal use, even if it results in higher gas consumption,” Howarth said.

“What the world demands is to move away from all fossil fuels as quickly as possible to a 100% renewable energy future.”

_{Translated by Luiz Roberto M. Gonçalves}